Electric-furnace.



PATENTED JULY 2, 1907.

F. T; SNYDBR. ELBGTRC FURNGE.

APPLIOATION FILED JULY 25, 1006.

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@M1/Mw@ PATENT@ JULY 2, 1907. P. T. SNYDER. BLEGTRIG FURNAGE. APPLICATION FILED JULY 25, 1906.

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PATBNTED JULY 2, 1907.

F. 'l'. SNYDER. BLEGTRG FURNAGE. APPLICATION FILED JULYzs, 1906.

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Nov. 859,137. PATENTED JULY 2, 1907. F. T. SNYDEE.

ELECTRIC FURNGE. Prummel FILED JULY 25. 190s.

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UNITED STALL FREDERICK T. SNYDER, OF OA COMPANY, Oli-CHICAGO,

Specification Lettere u, nemers,

C ELECCRC rultinl WEST VIRGINIA.

issienon oenroeii'riou or 11 Lelli .exilim-i Patented July 2, 1907.

pplieetion filed July Z5, 1906. Serial llo. 3Z?,635.

'for smelting ores, with particular reference to ores ol metals such as zinc, which are volatile at reduction.

The invention contemplates a structure in which the materials to be smelted may be preheated by the waste gases of the smelting operation and also by the heat conducted through the walls of the smelting chamber, and the liquid metal condensed from the vapors oi smelting may also be kept heated, the metallic product be reiined and the different metals separately collected, all in the same furnace and in what may be called the same operation.

The invention also resides in certain structural details which make for simplicity, ease and economy o` operation.

Two of the many forms which my invention may take are illustrated in the accompanying drawings, one type of furnace having the current led in by conductors dipping into the molten metal electrodes, while in the other type the materials to be heated constitute in themselves the secondary circuit of a transformer, cnrrent for heating said materials being induced therein by an alternating magnetic fieldset up by a suitableenergized primary coil.

Figure l .is a sectional elevation of the rst-inentioned type of furnace, in which current is led into the fused bath by conductors dipping into the molten elec trodes; Fig. 2 is a transverse section on line 2 2 oi Fig. l; Fig. 3 is a sectional plan view on line 3 3 of Fig. l; Fig. i is a sectional elevation of the transformertype of furnace; Fig. 5 is a transverse section on line 5 5 of Fig. 4; Fig. 6 is a transverse section on line 6-6 of Fig. 4.

'lhe same letters of reference indicate the saine parts Wherever theyappear. i

Referring iirst to Fig. l, the furnace is divided bya` horizontal partition e forming a preheating chamber f in the upper portion ofthe furnace, while the lower chamber. n cover fr. is supported at a distance above the feed opening el and overlaps said opening, so that mat is in the heating chamber, when pushed toward the iced opening, may reach up to said cover and form a seal to prevent the escape oi gas from the smelting chainber through the iced opening.

The smel ting chamber communicates by a passage 'nt over the t'op of the partition n with a combined condensing and refining chamber Z5, and from the last-mentioned chamber lues 7&1 k1 lead up thrbughhe end oiA the iurnace to the preheating chambery, so'ihat the uncondensed gaseous products et smelting, after passing through the condensing chamber, maybe burned in the preheating chamber to give up their energy and prepare the materials i'n the heating chamber for smelting. From the heating chamber the waste gases may pass oft through a stach s. 'lhe chamber It communicates with wells on the exterior of the furnace by means of passages p p1 through the sid walls thereof below the level oi the liquid metal in said chamber. One oi these passages is near the bottoni to withdraw the heavier metal7 while the other one is near the top to withdraw the lighter metal. For example, in. the smelting of leadzinc ore, some lead vapor may be carried over with the Zinc vapor into the condensing chamber, and the liquid metals in said chamber will there be refined, the lend settling out below the zinc and being Withdrawn through the passage pl, while the zinc may be withn dra-Wn through the passage jo near the top oi the ,chamber. l preferably provide a false roel k2 lor the con (lensing chamber 'to deflect the vapors coming from the smelting chamber into Vclose contact with the liquid metal in the chamber lt, to assist in condensing themetallic constituents oi the vapors` ln the form of furnace shown in Fig, l, the snielting chaml'ler is provided with a bridge Z1 in the central portion thereof, dividing the chamber into two metal re ceptacles or Wells a1 a2 on either side of the bridge, und

a transverse passage abovel the bridge containing slag` or other molten resistance material, the body oi slag extending across the bridge and joining the metal in the t vo receptacles o1 a2. The furnace is heated by elec-- tric current passed through the body of slag from one molten electrode to the other, and the material to be smelted is 'led from time to time through the `opening c onto the fused. bath of slag. lhe bridge?)v is preferably cooled internally by ineens of Water ilovvin'g from a conduit Current may be led into and out oi the furnace in the following manner: Each of the metal receptacles communicates with e well. such as the well d shown in Fig.

'2, on the exterior of the urnace, by rneans'o'a passoire ge extending under thewells. 'referably each. ofthe metal receptacles al communicates with wellen;

lili' secondary circuit aboutsaid core.

.sooner both sides of tlc i'urnace. The leading-in conductors ior the electric current may then be dipped into the molten metal in the external Wells, one at eachend ci the transverse passage, while the wells on the opposite sides of the furnace from said conductors Will be free to permit the molten metal to be ladlcd out from time to time as it accumulates. Preferably the leading-in conductors are brought to the furnace on opposite sides thereof, so that thev current will enter one end oi the transverse passage on one side of the furnace7 flou' through the slag in said transverse passage, and then leave by Way of the molten metal Well on the opposite side oi theurnace from which it entered. n each side oi the furnace there will therefore be an electrode Well and a free well from Which molten metal may be ladled. By reference to Fig. 3, it will be seen that the furnace chamber in plan is Iii-shaped, the two arms oi the being the metal receptacles'on opposite sides of the bridge, andthe cross oi the H being the transverse passage containing the slager resistance material in which the heat is chiefly developed.

Preferably the lower portion of the furnace is inclosed in a metal jacket or caisson at, which is joined at the bottom with a sheet metal base plate x1, forming a box in which the lower part oi the furnace body is con- 1"lained, giving additional strength to that portion of the structure which is iilled with the heavy molten metal. Troughs y y are shown extending around the sides of the jacket x, these troughs serving to contain iioufing Water iol' cooling purposes.

in the i'orm of furnace shown in Fig. 4 the smelting chamber isbuilt in accordance with my Pat-ent No. 325,859, dated July l0, 1906, the chamber' being provided With a bridge extending across the same, in which one arm of alaminated iron core is embedded, the chamber being continuous around and under the bridge, whereby the material in said chamber forms a closed. The lower arm of the transformer core is provided With a suitable primary induction Coil winding, which in Fig. 1i is indicated as inclosed Within the box w. In this form of furnace, when the primary coiliis supplied with alternating current oi suitable strength and voltage, an induced current will be set up in the materials in the chamber, constituting the secondary element of the transformer. The operation of this type o1" furnace is iully described in my prior patent above referred to.

it will be seen that in accordance with my invention the heat produced in smelting is utilized to the fullest extent, that which escapes through thepartition n serving to keep the molten metal in the condensing and refining chamber I; heated to the proper temperature, while the heat which escapes through the roof is communicated to the materials in the preheating chamber. rihe refining chamber k is further Iheated by .c gaseous products of sn1elting, which are introduced through the passage m, and the'non-condensed gases, after leaving the chamber le, give up additional heat in the preheating cirimberf, where they are burned.

ierabiy provide oil burners t t for heating the at starting, or for supplying additional heat when required. During the smelting operation the burners applied to the chamber Ztniay be shut off and the openings plugged up with clay. The burners lead# ing to the upper chamber f may be kept in operation during the sineiting, ii desired, to furnish additional heat.

This type oi iurnaceis particularly adapted for the smelting oi iead-zinc ores, as the furnace includes a preheater, a smelting chamber and a condensing and refining chamber, all arranged in series, so to speak, and all inelosed Within the same outer Walls. In smelting such ores the furnace charge will iirst be heated preliminarily in the chamber f, then i'cd 'through the opening c1 onto the iused bath in chamber a. lead and zine will be reduced, the lead sinking through the slag and adding to the molten metal in the wells el a2, While the zineis voiatilized and carried over through the passage m into the chamber 7c. Here the zinc will be condensed, together With any small quantities of lead vapor which may also have been carried over, and the metallic product will be refined' in the same chamber, the lead sinking to the bottom, from which it may be Withdrawn through passage p1, While the zinc collecting nearer the top may be Withdrawn through the passage p.

I claim:

1. The combination with un electric smeltiug furnace, of a transverse partition dividing the furnace, a smelting chamber being formed on one side oi' said partition, the upper part of the chumher'on the other side of said partition constituting n condensing chamber und the lower poi'- iion thereof u refining chamber. said several chambers being incioscd 'within the sume outer walls oi the furnace, and receiving heat i'roin the smelting chamber, a passage heini,r provided from the smelting chamber to the condensing chamber. and a flue for uncondensed of said condensing chamber.

2. An electric furnace having a smelting chamber comprising` :i transverse passage containing molten resistance material, und metal receptacles at the ends o1' said transverse passage, communicating with said transverse resistanccmassugc :ind also communicuting;r with the externer of the furnace on the sides thereof, in combination with conductors dipping into :in arm of euch of said metal receptacles. leaving the other arms thereof iicc'to permit tine metal io he ladicd outV fi. An electric furnace having @smelt-ing chamber which in pian is H-shnped. the two arms of the H communicating with the exterior oi the furnace und containing liquid metal, and the cross-passage being shailower thun suid arms and containing vresistance material iouting upon said liquid metal, in combination with electrodes dipping into the metal at the ends of said cross-passage.

4. The combination with an electric smelting furnace, of a transverse partition dividingr the furnace, a smeltiug chamber being formed on` one side of said partition, the upper part of the chamber on the other side constituting a condensing chamber and the lower portion thereof a refining chamber, a horizontal partition in the furnace forming a preheating chamber' above said smeitlng and condensA ing chambers having :in outlet lending to the smclting; chamber, said several Ichambers being inclosed by the sume outer walls to receive heut from the smelting chamber, u passage being provided from the smelting chamber vto the condensing chamber and n tine ior nncondensed gases leadinf,r ont of said condensing chamber.

in `Witness whereof, i, hereunto subscribe my name this 14th day of July A. D., 190C.

FREDERICK T. SNYDER.

Witnesses D, Tammo, A. H. Moons.

Here ther gases lendingy out, 

